2012 Vol. 9, No. 4
Atrial fibrillation (AF) is the most commonly encountered cardiac arrhythmia, and is a significant source of healthcare expenditures throughout the world. It is an arrhythmia with a very clearly defined predisposition for individuals of advanced age, and this fact has led to intense study of the mechanistic links between aging and AF. By promoting oxidative damage to multiple subcellular and cellular structures, reactive oxygen species (ROS) have been shown to induce the intra- and extra-cellular changes necessary to promote the pathogenesis of AF. In addition, the generation and accumulation of ROS have been intimately linked to the cellular processes which underlie aging. This review begins with an overview of AF pathophysiology, and introduces the critical structures which, when damaged, predispose an otherwise healthy atrium to AF. The available evidence that ROS can lead to damage of these critical structures is then reviewed. Finally, the evidence linking the process of aging to the pathogenesis of AF is discussed.
Objectives To compare long-term prognosis between complete revascularization (CR) and incomplete revascularization (IR) in elderly patients with acute coronary syndrome (ACS) who underwent percutaneous coronary intervention (PCI). Methods We prospectively enrolled patients ≥ 75 years with ACS and multi-lesion disease between January 2005 and December 2010 at our center (Institute of Geriatric Cardiology, Chinese PLA General Hospital). Baseline clinical characteristics, PCI parameters and long-term (12 to 78 months) outcomes including main adverse cardiac and cerebral events (MACCE) were compared between CR and IR groups. We used the Kaplan-Meier curve to describe the survival rates, and variables reported to be associated with prognosis were included in Cox regression. Results Of the 502 patients, 230 patients obtained CR, and the other 272 patients underwent IR. Higher SYNTAX score was an independent predictor of IR [Odds ratio (OR): 1.141, 95% confidence interval (95% CI): 1.066–1.221, P = 0.000]. A total of 429 patients (85.5%) were followed with a duration ranging from 12 months to 78 months. There were no significant differences in cumulative survival rates and event free survival rates between the two groups, even for patients with multi-vessel disease. Older age (OR: 1.079, 95% CI: 1.007–1.157, P = 0.032), prior myocardial infarction (OR: 1.440, 95% CI: 1.268–2.723, P = 0.001) and hypertension (OR: 1. 653, 95% CI: 1.010-2.734, P = 0.050) were significant independent predictors of long-term MACCE. Conclusions Given that both clinical and coronary lesion characteristics are much more complex in patients ≥ 75 years with ACS and multi-lesion disease, IR may be an option allowing low risk hospital results and meaningful long-term (12 to 78 months) outcomes.
Objective To evaluate the efficacy of preventive treatment (PT) on alveolar pulmonary edema (APE) of cardiogenic origin using a monitor based on principles of internal thoracic impedance (ITI) measurements. Methods We conducted blinded clinical trials on patients with ST-elevation myocardial infarction (STEMI) and monitored whether the condition would progress to APE. ITI was measured non- invasively by the Edema Guard Monitor (EGM, model RS-207) every 30 min. The measurement threshold for the diagnosis of APE was fixed at > 12% decrease in ITI from baseline as described in our methodology. The patients were divided into one group that received standard treatment after the appearance of clinical signs of APE without considering the prediction of APE by EGM devise (Group 1), and another group of asymptomatic patients in whom development of APE was predicted by using only EGM measurements (Group 2). The latter participants’ PT consisted of furosemide, intravenous nitroglycerine and supplemental oxygen. Results One-hundred and fifty patients with acute STEMI were enrolled into this study. Group 1 included 100 patients (53% males, age 64.1 ± 12.6 years). Treatment was started after the clinical appearance of overt signs of APE. Group 2 included 50 patients (54% males, age 65.2 ± 11.9 years) who received PT based on EGM measurements. Group 2 had significantly fewer cases of APE (n = 4, 8%) than Group 1 (n = 100, 100%) (P > 0.001). While APE was lethal in six (6%) Group 1 patients, PT resulted in prompt resolution of APE in all four (8%) Group 2 patients. Conclusion ITI is a useful modality for early diagnosis and PT of pulmonary edema of cardiogenic origin.
Objective The coronary artery calcium (CAC) score has been shown to predict future cardiac events. However the extent to which the added value of a CAC score to the diagnostic performance of myocardial perfusion imaging (MPI) by single photon emission computed tomography (SPECT) is unclear. The purpose of this study is to investigate the correlation between CAC score and SPECT in patients with suspected coronary artery disease. Methods A retrospective review of the CAC scores by use of the Agatston calcium scoring method and cardiac SPECT diagnostic reports was conducted in 48 patients, who underwent both coronary computed tomography (CT) and SPECT examinations due to suspected coronary artery disease. A Pearson correlation test was used to determine the relation between CAC scores and MPI-SPECT assessments with regard to the evaluation of the extent of disease. Results Forty-seven percent of the patients had CAC scores more than 100, while 42% of these patients demonstrated abnormal, or probably abnormal, MPI-SPECT. Of the 23% of patients with a zero CAC score, only 7% had normal MPI-SPECT findings. No significant correlation was found between the CAC scores and MPI- SPECT assessments (r value ranged from 0.012 to 0.080), regardless of the degree of coronary calcification. Conclusions There is a lack of correlation between the CAC scores and the MPI-SPECT findings in the assessment of the extent of coronary artery disease. CAC scores and MPI-SPECT should be considered complementary approaches in the evaluation of patients with suspected coronary artery disease.
Because it is safe and well tolerated, imatinib is a standard first-line therapy for chronic myeloid leukemia (CML). Although there have been sporadic reports of imatinib-induced cardiotoxicity, including left ventricle (LV) dysfunction and heart failure, the evidence for it is contradictory. Here, we reported a case of an 88-year-old male patient with CML developed decompensated heart failure following imatinib therapy. Four days after the initiation of imatinib, the patient developed orthopnea, edema and a pleural effusion accompanied by abdominal distension, nausea and vomiting. The chest X-ray film showed an enlarged cardiac profile. The echocardiogram demonstrated a decreased LV ejection fraction and enlarged left-side cardiac chambers. B-type natriuretic peptide concentrations were markedly increased. The patient recovered soon after the withdrawal of imatinib and introduction of comprehensive therapy for heart failure. Imatinib-induced cardiotoxicity in elderly patients is a potentially serious complication that merits further evaluation.
Hydrotherapy (exercise in warm water) is considered to be a safe and beneficial method to use in the rehabilitation of stable heart failure patients, but there is little information on the effect of the increased venous return and enhanced preload in elderly patients with biventricular heart failure. We present a case of an elderly man who was recruited to participate in a hydrotherapy study. We compared echocardiographic data during warm water immersion with land measurements, and observed increases in stroke volume from 32 mL (land) to 42 mL (water), left ventricular ejection fraction from 22% to 24%, left ventricular systolic velocity from 4.8 cm/s to 5.0 cm/s and left atrioventricular plane displacement from 2.1 mm to 2.2 mm. By contrast, right ventricular systolic velocity decreased from 11.2 cm/s to 8.4 cm/s and right atrioventricular plane displacement from 8.1 mm to 4.7 mm. The tricuspid pressure gradient rose from 18 mmHg on land to 50 mmHg during warm water immersion. Thus, although left ventricular systolic function was relatively unaffected during warm water immersion, we observed a decrease in right ventricular function with an augmented right ventricular pressure. We recommend further investigations to observe the cardiac effect of warm water immersion on patients with biventricular systolic heart failure and at risk of elevated right ventricular pressure.
Objective To investigate the characteristics of ectopic automaticity and cation current (If) of cardiac myocytes from pulmonary vein sleeves (PVs) in canines with atrial fibrillation. Methods The canines (8–10 years old) were subjected to long-term, rapid atrial pacing (RAP) for 10 weeks, which induced the atrial fibrillation model. Disassociation of PVs of canines yielded single cardiac myocytes from a Landengorff column. Action potential, If and hyperpolarisation activated cyclic nucleotide-gated (HCN) currents were measured with the patch-clamp technique. Results Compared with the control group, cardiac myocytes from the RAP canine PVs had spontaneous diastolic depolarization, shorter action potential duration, and larger If densities. In the group of RAP cells, the half maximal activation potential (V1/2) was found to be less negative (?105.5 ± 5.2 mV) compared to control cells (?87.3 ± 4.9 mV). Current densities of If were increased significantly by β-adrenergic receptor stimulation with isoproterenol and caused an acceleration of current activation. In contrast, If currents in the RAP were reduced by carvedilol, a selective beta-adrenergic receptor. Another important finding is that HCN4-based channels may make a significant contribution to If in PVs cells, but not HCN2. Meanwhile, HCN4 current significantly increases in canine PVs cardiac myocytes with RAP. Conclusions The spontaneous action potential and larger If current were observed in the PVs cardiac myocytes using RAP, which may contribute to more ectopic activity events to trigger and maintain atrial fibrillation.
Objectives The aim of this study was to evaluate the relationship between inflammation and development of atrial fibrillation (AF) in patients with hyperthyroidism. Methods A total of 65 patients with newly diagnosed hyperthyroidism, 35 of whom were in sinus rhythm and 30 of whom in AF. Thirty five age- and gender-matched patients in a control group were included in the study. Factors associated with the development of AF were evaluated by multivariate regression analysis. Results Factors associated with AF in multivariate analysis included high sensitivity C reactive protein [(HsCRP); odds ratio (OR): 11.19; 95% confidence interval (95% CI): 1.80-69.53; P = 0.003], free T4 (OR: 8.76; 95% CI: 2.09–36.7; P = 0.003), and left atrial diameter (OR: 1.25; 95% CI: 1.06–1.47; P = 0.008). Conclusions The results of the present study suggest that high sensitivity C reactive protein, an indicator of inflammation, free T4 and left atrial diameter are associated with the development AF in patients with hyperthyroidism.
Objective To evaluate the prognostic value of chronic kidney disease (CKD) in elderly Chinese patients with chronic heart failure (CHF). Methods The study consisted of 327 elderly patients with CHF. All-cause mortality was chosen as an endpoint over the median follow-up period of 345 days. Cox regression analysis was used to identify the risk factors of mortality. Results The median age of the entire cohort was 85 years (60?100 years). The mortality for 168 elderly patients with CHF and CKD (51.4% of entire cohort) was 39.9% (67 deaths), which was higher than the mortality for CHF patients without CKD [25.2% (40/159 deaths)] and the mortality for entire cohort with CHF [32.7% (107/327 deaths)]. The Cox regression analysis showed that old age [hazard ratio (HR): 1.033; 95% confidence interval (95% CI): 1.004?1.064], CKD (HR: 1.705; 95% CI: 1.132?2.567), CHF New York Heart Association (NYHA) class IV (HR: 1.913; 95% CI: 1.284?2.851), acute myocardial infarction (AMI) (HR: 1.696; 95% CI: 1.036?2.777), elevated resting heart rate (HR: 1.021; 95% CI: 1.009?1.033), and decreased plasma albumin (HR: 0.883; 95% CI: 0.843?0.925) were independent risk factors of mortality for elderly patients with CHF. Conclusions CKD was an independent risk factor of mortality for elderly Chinese patients with CHF.
Background Pulmonary arterial systolic pressure (PASP) can be estimated with transthoracic echocardiography. However, the sig?nificance of raised PASP on routine echocardiography is uncertain. In this study, we evaluated the mortality and hospitalization rates of subjects with raised PASP in a cohort of patients referred directly by their general practitioners for routine outpatient (open access) echocardiography for further analysis of suspected heart failure. Results A total of 485 subjects were referred for open access echocardiography at our hospital in 2002. A cohort of 209/485 (43%) consecutive subjects with measurable tricuspid regurgitation were followed for a minimum of five years investigating hospitalization rates and survival. Some 62 of 209 (30%) subjects had pulmonary hypertension (PH). Subjects with PH were significantly more likely to have four or more hospital admissions (22% vs. 8%; P 30 days of cumulative hospital stay over five years (29% vs. 13%; P P = 0.003), while moderate to severe PH was an independent predictor of mortality (hazard ratio: 4.31; 95% confidence interval (95% CI): 1.51–12.30). Records from the Office of National Statistics revealed that subjects with PH were more likely to have chronic lung diseases recorded as immediate or contributory causes of death (50% vs. 14%; P Conclusions PASP ≥ 36 mmHg on routine echocardiography is associated with recurrent hospital admissions, prolonged hospitalizations and increased cause of mortality. Therefore, the diagnosis of PH on echocardiography deserves further clinical evaluation, with future studies designed at defining a suitable diagnostic strategy.
During the last 20 years, the management of heart failure has significantly improved by means of new pharmacotherapies, more timely invasive treatments and device assisted therapies. Indeed, advances in mechanical support, namely with the development of more efficient left ventricular assist devices (LVADs), and the total artificial heart have reduced mortality and morbidity in patients awaiting transplantation, so much so, that LVADs are now approved of as a strategy for destination therapy. In this review, the authors describe in detail the current basic indications, functioning modalities, main limitations of surgical LAVDs, total artificial heart development, and percutaneous assist devices, trying to clarify this complex, but fascinating topic.
High density lipoproteins (HDL) promote the efflux of excess cholesterol from peripheral tissues to the liver for excretion. This ability is responsible for the most relevant anti-atherogenic effect of HDL. The ability of HDL to promote cholesterol efflux results also in the modulation of a series of responses in the immune cells involved in atherosclerosis, including monocyte-macrophages, B and T lymphocytes. Furthermore, during inflammation, the composition of this class of lipoproteins varies to a large extent, thus promoting the formation of dysfunctional HDL. The aim of this review is to discuss the emerging role of HDL in modulating the activity of immune cells and immune-inflammatory mediators during atherogenesis.
As a member of Glycoprotein IIb/IIIa (GP IIb/IIIa) inhibitors, Tirofiban had been shown to improve myocardial reperfusion and clinical outcomes in patients undergoing percutaneous coronary intervention (PCI), but the optimal timing of administration of Tirofiban remains unclear. In order to compare the effects of upstream versus downstream administration of Tirofiban in Chinese patients with mid to high risk, non-ST elevation acute coronary syndrome (ACS) referred for PCI, a multicenter, randomized, controlled, prospective study will be conducted. A total of 500 mid to high risk, non-ST-segment elevation myocardial infarction (NSTEMI) ACS patients will be recruited for this study. Patients will be randomized to Tirofiban upstream administration group (initiated 12 h before PCI) and Tirofiban downstream administration group (initiated at cath-lab after angiography). Thrombolysis in myocardial infarction (TIMI) flow grades, TIMI myocardial perfusion grades (TMPG), and Corrected TIMI frame counting (CTFC) before and after PCI, as well as clinical outcomes during the hospital stay, and within 30 days after PCI will be compared between the two groups. This study will provide evidence on the optimal timing for initiating administration of Tirofiban in mid to high NSTEMI ACS subjects undergoing PCI.
Objective To assess the secular trends in the etiology and comorbidity of patients hospitalized with congestive heart failure (CHF). Methods Data of 7,319 patients (mean age 59.6 years, 62.1% male) with a primary discharge diagnosis of CHF, hospitalized from January 1, 1993 to December 31, 2007 at the Chinese People’s Liberation Army (PLA) General Hospital were extracted and analyzed. These patients were divided into three groups according to hospitalization period: 1993–1997 (n = 1623), 1998–2002 (n = 2444), and 2003–2007 (n = 3252). The etiological characteristics and comorbidities were assessed. Results Over the study period, the proportion of patients with ischemic heart disease (IHD) increased from 37.2% during the period 1993–1997 to 46.8% during the period 2003–2007, while that with valvular heart disease (VHD) decreased from 35.2% during the period 1993–1997 to 16.6% during the period 2003–2007 (both P P P Conclusions This study implies that IHD has became a more common etiology of CHF, while VHD has deceased as an etiology of CHF in Chinese patients during the last two decades.